Patent DE-102010014552-A1 (DE)
Title: Coating a substrate surface using a plasma beam or plasma beams, comprises directing a beam of an atmospheric low-temperature plasma to the substrate surface according to respective plasma coating nozzle in opposition to thermal injection
Inventor: BRUMMER TIMO
IPC: C23C4/12
Filed: 2010-04-10
Abstract: The method for coating a substrate surface (4) using a plasma beam (2) or plasma beams, comprises directing a beam of an atmospheric low-temperature plasma to the substrate surface according to a respective plasma coating nozzle in opposition to thermal injection, and feeding the beam of the atmospheric low-temperature plasma to a homogeneous coating liquid consisting of carrier liquid and fine-grained powder or a liquid mixture with solid portions in dosed quantity for the coating using a pump- or a dosing system via a homogenization container with a homogenization system. The method for coating a substrate surface (4) using a plasma beam (2) or plasma beams, comprises directing a beam of an atmospheric low-temperature plasma to the substrate surface according to a respective plasma coating nozzle in opposition to thermal injection, and feeding the beam of the atmospheric low-temperature plasma to a homogeneous coating liquid consisting of carrier liquid and fine-grained powder or a liquid mixture with solid portions in dosed quantity for the coating using a pump- or a dosing system via a homogenization container with a homogenization system, where the solid portions from the coating liquid receives an adhesive bond with the substrate surface. The coating of the substrate surface statistically or dynamically takes place by moving a plasma generator (1) with the plasma beam over the substrate surface or by moving the substrate surface into the plasma beam. During and after the statistical coating process, the substrate temperature raise is below 900[deg] C at a distance of 5-20 mm between the plasma-coating nozzle and the substrate surface. During and after the dynamical coating process, the substrate temperature raise is below 100[deg] C at a distance of 5-20 mm between the plasma-coating nozzle and the substrate surface and a feed rate of plasma beam or substrate surface with 1-10 meter per minute. The grain size of the solid portions or the admixed fine-grained powder or the powder mixture in the coating liquid is 1-100 nanometers. The plasma develops in a plasma nozzle under supplying a working gas and/or an evaporatable liquid and generating a discharge through the high voltage or electrical and/or electromagnetic coupling. The primary plasma is blown out to the substrate surface through a nozzle shaped opening (3) of the plasma generator, where the coating liquid is directly introduced as fine particles into the secondary plasma beam outflowing to the nozzle opening using a flat spray nozzle. The coating liquid within the nozzle is entered into an area of the plasma nozzle tapering itself to the nozzle opening. The coating liquid is entered into the primary plasma through an internal electrode. Air or nitrogen is used as working gas (7) or plasma gas. The low-temperature plasma is accelerated to the directed primary plasma beam at the transition to the ambient using the plasma nozzle after the formation of an electrically or electromagnetically generated primary non-equilibrium plasma in a partially closed plasma generator and consequently forms the secondary plasma at ambient pressure according to the nozzle. The substrate surface is cleaned and/or micro-structured or nano-structured by the secondary plasma beam without supplying the coating liquid. For generating the primary plasma, a high-frequency alternating current or direct current is used with a frequency of 10 kHz to 10 GHz and an electric power of less than 5 kW.